PCT Workshop Before you leave the office

Transcription

1 Before you leave the office

2 Documentation Suitable Equipment Calibration Training Preparation

3 Documentation Currently documentation for the scheme consists of: Association Of Noise Consultants PCT Registration Scheme Handbook February 2016 Good Practice Guide - ANC Registration Scheme For Precompletion Testing Version New version of the Good Practice Guide available today Iain Critchley to discuss later!

4 Documentation Relevant Standards Which standard should measurements be made to? BS EN ISO 140 Series OR BS EN ISO 16283

5 Documentation BS EN ISO 140 Series NOT BS EN ISO Relevant Standards ADE refers to dated versions of the standard and so ISO 140 (4 & 7) remain However, BS EN ISO 16283:2014 Part 1 (and Part 2 for impact) should be used as guidance, replacing BS EN ISO :2004 for special situations in the field, which is also now withdrawn.

6 Documentation Relevant Standards BS EN ISO 16283:2014 Parts 1&2 usefully permit the tester to remain in the test room and describe several manual scanning techniques, which the withdrawn ISO 140 Parts 4 and 7 do not. BS EN ISO 16283:2014 Parts 1&2 also describe impulsive sound sources for reverberation time measurement, using reverse integration methods, according to BS EN ISO :2008, which the withdrawn ISO 140 Parts 4 and 7 do not.

7 Suitable Equipment Sound Level Meter Type 0 or 1 Class for octave and fractional octave filters On-site calibrators should comply with accuracy Class 1 Sound Source White/Pink Noise Suitable signal chain Loudspeaker/amplifier Omni-directional or Cabinet (BS EN ISO 140-4) Tapping Machine

8 Is my calibration valid? How frequent? Where? What needs to be checked? What standards?

9 What Needs to be Calibrated and When? Sound Level Meters (inc. microphone & pre-amp)? Calibrators? Tapping Machines? Sound Source? Loudspeaker? Loudspeaker Stand?

10 What Needs to be Calibrated? Sound Level Meters two years (or if pre-amp/microphone changed) Calibrators two years with annual check or every year Tapping Machines conformance check two years Sound Source none but Loudspeaker none but Loudspeaker Stand tape measure

11 Calibrators Calibrators to at least traceable standards, by a competent laboratory at intervals not exceeding one year. Alternatively, calibrator in-house against a known calibrator of the same type which has been calibrated by the competent laboratory within the previous twelve month period. In that case the calibration interval between traceable laboratory calibrations, for the calibrator, can be every two years. The in-house calibration checks must be formally recorded and the records supplied with the other instrument calibration certificates when requested as part of a company audit.

12 What is a Competent Laboratory?

13 What is a Competent Laboratory? The scheme does not require members to only use UKAS accredited laboratories A valid certificate of calibration should be obtained from a calibration laboratory that demonstrates competence, measurement capability and traceability to National standards. It is the Members responsibility to satisfy themselves of this as the ANC does not provide an Approved List of non-ukas laboratories.

14

15 Common Calibration Audit Issues Make sure your list of equipment includes the calibration certificate number and date Double check to make sure they are correct Check again No, really, check it again

16 Is my sound source stable? The measurement procedure depends on the source room signal being constant. Check periodically under controlled conditions that the source level measured over two 30 second periods does not vary by more than 1 db in any ⅓-octave band in the measured frequency range when neither microphone or loudspeaker are moved. If the equipment is found not to comply, the test results which have been taken since the previous check will be thrown into doubt; therefore a suitable period should be chosen to minimise this risk

17 Is my sound source stable? wireless radio links The same procedure should be used for both source and receiver room measurements. The tester should be satisfied that the system has the capability to handle the maximum signal that is transmitted, over the required frequency range and that it is stable. Their use should be included in all assessments of source stability and estimates of uncertainty.

18 Using two sound sources If more than one sound source is used simultaneously, the output power of each source must be similar in each relevant frequency band. The standard requires that sound sources must be similar for the two loudspeaker method. Taken to mean similar type; e.g. cabinet or omni loudspeaker with similar noise source. Most important aspect is that output power must be similar in each frequency band

19 Training Can you use the equipment Can you use the spreadsheet or software to carry out the calculations Are you sure you know all of the setup requirements for the meter to feed into the software Are you up to date with methodology and standards

20 Can I use it? It is OK to use hired equipment but please make sure you have had a trial run or are familiar with the equipment In-house witness checks should be carried out regularly to pass on best practice For example, if specific meter settings are required for proprietary software to work, be sure there is a method for checking the settings

21 Preparation Have you been able to plan the rooms to be tested using drawings and calculate volumes? Are you confident about the construction types and how many groups there are? Will the site be quiet? Is there power/adequate lighting? Do they know you re coming? Do you know where it is? Is there parking? Have they paid

22 Preparation Is the equipment working? Try before you leave Do you have spares for possible problems, batteries, etc Adequate stock of survey sheets, etc Calibrate the meter and tapping machine before leaving the office Repeat on site Do you have a checklist

23 Do they know I m coming?

24